Local governments such as municipalities and transportation offices regularly need to estimate crowds and traffic in certain locations and to update traffic control maps accordingly. These plans are updated in maps and dictate certain changes in traffic routing during major events, accidents and evacuation, such as Sunday markets, movie theater shooting or some major construction. If planned well, the updates can be finished in advance and be publicly advertised to citizens.
However, there are cases where major events occur such as pilgrimage and evacuation during terrorist attack, where it becomes very difficult to predict the changes in routes, and update traffic maps and estimate crowds instantaneously to reflect those real-time changes. In these situations, decisions have to be made at real-time and organizers need to make instant choices whether to close the road segment, turn it to one-way, reduce entries, or classify entry based on specific type of vehicles.